In the web offset printing process, a continuous web of paper is transported through a printing press. Near the beginning of the press, one or more printing units apply ink to the web to repeatedly create a pattern, or impression, of text and images. At the end of the press, a web conversion apparatus, such as a sheeter or folder, may be used to convert a web into individual products.
A sheeter converts a continuous web of material into individual sheets of material. Typcially, a sheeter produces a single sheet of paper that will be used for a poster, book cover or be subsequently processed. Sheeters are known for example from the firm Innotech, which is located in Valley Cottage, N.Y. Innotech manufactures web press auxiliary equipment, including some equipment that involves transporting webs on-edge.
A folder converts a continuous web of material into individual folded products. In a typical folder, the web and signatures travel a considerable distance in the vertical direction. To accommodate this vertical travel, folders are often quite tall, with some exceeding 35 feet in height. A tall folder requires a printing press facility with high ceilings. A tall folder is also more difficult to operate because reaching the various apparatus components requires climbing up and down many stairs. To reduce the height of folders, back-to-back formers and side-by-side formers have been employed.